Ref:

Generate Crystal Reports using Strongly Typed DataSet in ASP.Net using C# and VB.Net

HTML

<form id="form1" runat="server">
Please Select Year

<asp:DropDownList ID="ddlYears" runat="server" OnSelectedIndexChanged="OnSelectedIndexChanged" AutoPostBack="true">
    <asp:ListItem Text="1996" Value="1996" />
    <asp:ListItem Text="1997" Value="1997" />
    <asp:ListItem Text="1998" Value="1998" />
</asp:DropDownList>

<CR:CrystalReportViewer ID="CrystalReportViewer1" runat="server" AutoDataBind="true" />
</form>

Namespaces

using System.Data;
using System.Configuration;
using System.Data.SqlClient;
using CrystalDecisions.CrystalReports.Engine;

C#

protected void Page_Load(object sender, EventArgs e)
{
    if (!this.IsPostBack)
    {
        BindCrystalReport();
    }

}

private void BindCrystalReport()
{
    ReportDocument crystalReport = new ReportDocument();
    crystalReport.Load(Server.MapPath("~/CustomerReport.rpt"));
    Customers dsCustomers = GetData(@"SELECT * FROM Customers customers
                                    INNER JOIN Orders orders ON customers.CustomerId = orders.CustomerId 
                                    WHERE DATEPART(YEAR,orders.OrderDate) = @Years");
    crystalReport.SetDataSource(dsCustomers);
    CrystalReportViewer1.ReportSource = crystalReport;
}

protected void OnSelectedIndexChanged(object sender, EventArgs e)
{
    BindCrystalReport();
}

private Customers GetData(string query)
{
    string conString = ConfigurationManager.ConnectionStrings["constr"].ConnectionString;
    SqlCommand cmd = new SqlCommand(query);
    using (SqlConnection con = new SqlConnection(conString))
    {
        using (SqlDataAdapter sda = new SqlDataAdapter())
        {
            cmd.Connection = con;
            cmd.Parameters.AddWithValue("@Years", this.ddlYears.SelectedItem.Value);
            sda.SelectCommand = cmd;
            using (Customers dsCustomers = new Customers())
            {
                sda.Fill(dsCustomers, "DataTable1");
                return dsCustomers;
            }
        }
    }
}

Screenshot